* Pure Compound: A pure compound is made up of only one type of molecule. It would have a consistent color and appearance throughout.

* Mixture: A mixture is a combination of two or more substances that are not chemically bonded. The substances retain their individual properties, which is why you can see distinct white specks and blue in this powder.

* Element: An element is a pure substance made up of only one type of atom.

* Solution: A solution is a homogeneous mixture where one substance (solute) is dissolved into another (solvent). You wouldn't be able to see separate specks in a solution.

Since the powder has visible, distinct parts, it's clearly a mixture.